After knocking on the door, there is in fact no reply from the other side. To continue from there I've assumed you head down the northern passage from here.
To the north, the group finds an open cavern, roughly 30 feet wide on each side. A pool of murky green-tinted water fills the eastern and western sides of the room. As the group approaches, they can see that the water bubbles and fumes constantly, the smell of sulfuric acid in the air.
In the distance, what sounds like rabid animals fighting echoes down the halls, but before there's time to take notice of what's happening far away - something much closer charges across the cavern. Two wolf-men, both licking their open wounds and battered bodies stand at the opposite edge of the cavern.
They take notice of the group at approximately the same time the group notices them in the shadows of the cavern.
Tyrla, Avril, Warren, Larian: Both of these creatures have multiple open wounds and cuts, but they appear to be healing quickly. Very quickly.
Tyrla, Avril, Larian, Siobhan: These creatures are the victims of lycanthropy, with all that entails. These particular creatures are fast, strong, and fairly resiliant. They regenerate from all damage not inflicted with silver weapons, fire, or acid. They take subdual damage from all other sources.
Initiatives
Warren 27
Avril 21
Pender 20
Larian 20
Tyrla 19
Siobhan 19
Werewolves 18
(That's some high dice on all sides...)
For some reason the new version of openoffice changed some of the behavior and it didn't copy everything exactly how I had it. Regardless, you can choose to start in any square in the 11,12,13 rows that's light gray (regular terrain). The dark gray is the cavern walls. The greenish color represents the pooled up acid.
If you start your turn in a square adjacent to the acid, you must make a fortitude save (DC 14) or be nauseated. Nauseated creatures are unable to attack, cast spells, concentrate on spells, or do anything else requiring attention. The only action such a character can take is a single move action per turn.
If you end up in the acid somehow, it's 3d6 damage (reflex DC 14 for half). It's not particularly deep so it only counts as difficult terrain.